1. Field of the Invention
The present invention relates to braking/driving force controlling apparatus and method for an automotive vehicle and, more specifically, relates to the braking/driving force controlling apparatus and method suitable for the automotive vehicle to be parked.
2. Description of the Related Art
A Japanese Patent Application First Publication No. Heisei 10-278825 published on Oct. 28, 1998 which corresponds to a U.S. Pat. No. 5,931,252 issued on Aug. 3, 1999 exemplifies a previously proposed automatic steering system for an automotive vehicle in which the vehicle moves in accordance with a locus predefined at a time of an automatic steering during a vehicular parking. In a case where a vehicle creep speed falls out of a predetermined speed range, the automatic steering system urges a vehicle driver to carry out a brake manipulation or accelerator manipulation through a liquid crystal display or speaker.
In the previously proposed automatic steering system disclosed in the above-identified Japanese Patent Application First Publication, the driver is informed to carry out the brake manipulation or accelerator manipulation.
Hence, for example, in a case where the vehicle is needed to be parked while ascending a slope, a suitable vehicle creep speed is often not obtained merely by the brake manipulation. In this case, the driver needs to depress an accelerator pedal to once raise the vehicle speed up to a predetermined vehicle speed and, thereafter, needs to depress a brake pedal in accordance with an operation command from the previously proposed automatic steering system. In this way, the driver needs to change the pedal to be depressed to drive the vehicle. The driving operation is troublesome for the driver.
It is, hence, an object of the present invention to provide improved braking/driving force control apparatus and method for an automotive vehicle which can achieve an easy driving operation even if the vehicle parking is carried out at any place.
According to one aspect of the present invention, there is provided a braking/driving force controlling apparatus for an automotive vehicle, comprising: a state discriminating section that discriminates between a parking state in which a manipulation for the vehicle to be parked is carried out and a non-parking state in which no manipulation for the vehicle to be parked is carried out; a manual input section that is enabled to be manipulated; a manipulated variable detecting section that detects a manipulated variable of the manual input section; a target vehicle speed generating section that generates a constant target vehicle speed corresponding to the manipulated variable detected by the manipulated variable detecting section in a case where the state discriminating section discriminates the parking state; a braking/driving force calculating section that calculates a vehicular braking/driving force for a present vehicle speed to become the target vehicle speed; and a braking/driving force controlling section that controls the vehicular braking/driving force on the basis of the vehicular braking/driving force calculated by the braking/driving force calculating section.
According to another aspect of the present invention, there is provided a braking/driving force controlling apparatus for an automotive vehicle, comprising: a state discriminating section that discriminates between a parking state in which a manipulation for the vehicle to be parked is carried out and a non-parking state in which no manipulation for the vehicle to be parked is carried out; a manual input section that is enabled to be manipulated; a manipulated variable detecting section that detects a manipulated variable of the manual input section; a target vehicle speed generating section that generates a target vehicle speed based on the manipulated variable detected by the manipulated variable detecting section; a braking/driving force calculating section that calculates a vehicular braking/driving force for a present vehicle speed to become the target vehicle speed generated by the target vehicle speed generating section; and a braking/driving force controlling section that controls a vehicular braking/driving force on the basis of the vehicular braking/driving force calculated by the braking/driving force calculating section, and wherein the target vehicle speed generating section generates a constant target vehicle speed when the manipulated variable detected by the manipulated variable detecting section is zero and the braking/driving force calculating section calculates a new target braking/driving force by combining the vehicular braking/driving force for the vehicle speed to become the constant target vehicle speed with the vehicular braking/driving force based on the manipulated variable detected by the manipulation detecting section.
According to a still another aspect of the present invention, there is provided a braking/driving force controlling method for an automotive vehicle, comprising: discriminating between a parking state in which a manipulation for the vehicle to be parked is carried out and a non-parking state in which no manipulation for the vehicle to be parked is carried out; detecting a manipulated variable of a manual input section that is enabled to be manipulated; generating a constant target vehicle speed corresponding to the detected manipulated variable in a case where the parking state is discriminated; calculating a vehicular braking/driving force for a present vehicle speed to become the target vehicle speed; and controlling the vehicular braking/driving force on the basis of the calculated vehicular braking/driving force.
This summary of the invention does not necessarily describe all necessary features so that the invention may also be a sub-combination of these described features.